Jupiter Turned Comet Into "Moon" for 12 Years

Sixty years ago, Jupiter carried on a 12-year fling with an extra "moon" then casually cast it aside—and the gas giant will likely do it again within decades, scientists announced today.

In 1949 the massive planet's gravity pulled in comet 147P/Kushida-Muramatsu and held it in orbit until 1961, according to an international team led by Katsuhito Ohtsuka of the Tokyo Meteor Network.

The 1,300-foot-wide (400-meter-wide) comet's stint as a so-called temporary satellite was revealed when the researchers used calculations taken since the comet's 1993 discovery to determine the space rock's past course.

"We can be fairly sure that the comet orbited Jupiter once or twice before escaping it," said team member David Asher of the U.K.'s Armagh Observatory.

Source: nationalgeographic.com



This is quite an interesting new discovery I think, and made by a team comprising some of the best known researchers in the field of meteors and comets. David Asher in particular, who helped pave the way for the science of meteor forecasting by predicting the Leonid meteor storms/outbursts at the turn of this century with previously unheard of accuracy, thanks to their work using/designing powerful computer models that can simulate the orbits of comets and the particles (meteoroids) that make up the dust trails which cause meteor showers when Earth travels through them in it's orbit around our Sun.

That same advance in computer modeling has no doubt contributed to this latest discovery. My congratulations to David Asher and all the people that contributed to this and their past work towards unraveling the mysteries of the solar system we live in!

I was wondering what sort of orbit it might have been and found this diagram.
Pretty cool, a couple of eccentric orbits around Jupiter, then one around the L1 point, then on its way.


www.universetoday.com...

[edit on 9/15/2009 by Phage]

reply to post by Phage


That's a great find and addition to the thread Phage. Very cool as you say! Thanks for posting that.

It's amazing that after all that (gravitational forces must have been pretty intense!) something survived to be observed from here on Earth in 1993. I wonder how close it came to Jupiter compared to Shoemaker-Levy 9's prior to last encounter with it!?

That same advance in computer modeling has no doubt contributed to this latest discovery. My congratulations to David Asher and all the people that contributed to this and their past work towards unraveling the mysteries of the solar system we live in!

Several short period comets have been identified to date that entered into temporary orbit around Jupiter. The most famous example would be D/1993 F2 Shoemaker-Levy 9 (the comet that fragmented and slammed into the planet in July 1994). Whilst calculating the past motion of a comet with this kind of orbit is extremely difficult, it is possible that it was in temporary orbit around Jupiter for nearly a century!

Whilst this study will have used extremely accurate computer modelling, it is worth noting that I can simulate the orbits of comets on my home PC (using an amazing piece of software called Dance of the Planets). I have simulated the past motion of Shoemaker-Levy 9 using this software, and even though this wouldn't have been as accurate as research grade studies, it was good enough to show that the comet nearly collided with the planet in 1970, and again in 1972.

I have not integrated the motion of 147/P Kushida-Muramatsu backwards in time, but I suspect that I would be able to simulate the 1949-1961 temporary orbit of Jupiter on my PC. I have accurate orbital elements for the comet from its 1993 discovery apparition, so it might be an interesting exercise....

WOW! dance of the panets! i used to see that advertised all the time in sky&telescope magazines, late 80's early 90's!!! IS the program still around for sale today?

ARC Science Simulations do still sell Dance of the Planets (now provided on CD instead of floppy disks), but there is no guarantee that it will work properly on your current PC. Check out the website....

www.arcscience.com